Field of the Invention
The present invention relates to an organic light emitting display device and a method of manufacturing the same.
Discussion of the Related Art
As a type of new flat panel display device, organic light emitting display devices are self-emitting display devices, and have a better viewing angle and contrast ratio than liquid crystal display (LCD) devices. Also, since the organic light emitting display devices do not need a separate backlight, the organic light emitting display devices can be made lighter and thinner with excellent power consumption compared to LCD devices and the other flat panel display devices. Furthermore, the organic light emitting display devices are driven with a low direct current (DC) voltage, have a fast response time, and are low in manufacturing cost.
In organic light emitting display devices, an electron and a hole are respectively injected from a cathode and an anode into an emitting material layer, and, when an exciton in which the injected electron and hole are combined is shifted from an excited state to a base state, light is emitted. In this case, the types of organic light emitting display devices are categorized into a top emission type, a bottom emission type, and a dual emission type according to an emission direction of light, and categorized into a passive matrix type and an active matrix type according to a driving type.
Specifically, the organic light emitting display device includes a first electrode (anode), a hole transporting layer, an emitting material layer including a red organic emission pattern, a green organic emission pattern, and a blue organic emission pattern, an electron transporting layer, and a second electrode (cathode), which are formed in each of a red pixel area, a green pixel area, and a blue pixel area.
In the organic light emitting display devices having such structure, when a voltage is applied to the first and second electrodes, a hole moves to the emitting material layer through the hole transporting layer, an electron moves to the emitting material layer through the electron transporting layer, and the hole and the electron are combined in the emitting material layer, thereby emitting light.
In the organic light emitting display devices, a fine metal mask (FMM) process is used for patterning the emitting material layer between two electrodes disposed on a substrate. Numerous FMM processes may be performed to manufacture an organic light emitting display device. When FMM processes are applied to different pixels, a fine metal mask needs to be moved and aligned for different pixels. During that process, the fine metal mask may not be properly aligned which may cause certain defects. Also, each FMM process may require alignment of a mask over different pixels of an organic light emitting display device. Such alignment may require substantial time and labor, which adds manufacturing expenses and lengthens manufacturing time. Moreover, a mask used in FMM processes is costly. Accordingly, there is a need to reduce a number of FMM process and simplify manufacturing processes.